Assessment of the utility of ultrasonography with high-frequency transducers in the diagnosis of entrapment neuropathies

The primary aim of this paper was to assess the relevance of high-frequency ultra-sound examination in qualifying patients for either surgical or conservative treatment of peripheral entrapment neuropathies. The study was conducted in a group of 55 patients aged 7-83 (mean age 43.6), including 28 males and 27 females, who in 2009-2011 were referred to an ultrasound examination due to a clinical suspicion of entrapment neuropathies. For the purposes of the analysis, the patients were divided into four groups: carpal tunnel syndrome (1), ulnar nerve entrapment (2) (cubital tunnel syndrome and Guyon's canal syndrome), posterior interosseous nerve syndrome (3) and other entrapment neuropathies (4). The cases of isolated idiopathic carpal tunnel syndrome were excluded from the analysis. All patients underwent the interview, physical examination and ultrasound examination. Ultrasound examinations were performed with Esaote MyLab 50 and MyLab 60 systems using high-frequency broadband linear transducers: 6-18 MHz. Sixty-seven percent of patients (37 persons) underwent a neurophysiological test. Nerve echostructure, its hyperemia as well as nerve cross-sectional area or, in the case of small nerves, diameter were assessed in all patients. Furthermore, the following were assessed in individual groups: notch sign in group 1, nerve instability in a dynamic ultrasound examination in group 2, nerve angulation in a dynamic ultrasound examination and tenderness on nerve compression at the site of the visualized pathology in group 3. The analyses of the collected material were performed by means of descriptive statistics. The results of clinical and surgical verification were consistent with ultrasound findings in 96.4%. The results indicate that high-frequency ultrasonography is a valuable method in qualifying patients for various types of treatment of peripheral neuropathies resulting from compression.